Re: Locate good data point

[Andrew Wittenberg <andyw@xxxxxxxxxxxxxxxxxxxx>]

On Thu, 19 Jul 2001, Jens-Olaf Beismann wrote:

> I'm trying to locate the i-index of the westernmost ocean point at a
> given latitude.

Hi Jens-Olaf,

Here's my two cents worth -- a demonstration with the ETOPO60 dataset that
comes with Ferret.  This does only what you say, i.e. the westernmost
points in the Gulf of Mexico and Hudson Bay are returned.  If you want the
east edge of Florida and the west edge of the Labrador Sea, then you'll
have to edit the land mask to eliminate ocean points west of there.

use etopo60
set region/x=100w:0e/y=0n:80n
let ival = i+0*(IF rose LT 0 THEN rose)
set v ul; shade rose
set v ur; shade/title="ocean i values" ival 
set v ll; plot/trans/title="westernmost" ival[x=@min]
set v lr; plot/trans/title="easternmost" ival[x=@max]

Good luck!

Andrew

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Andrew Wittenberg          Program in Atmospheric and Oceanic Sciences
andyw@splash.princeton.edu                        Princeton University
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